Maartens Notebook

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Besides writing software, both for fun and for profit, I’m also a conference speaker. Below is a list of talks I have delivered so far. A list of events where each talk was delivered is also included.

Contents and titles vary over time, as I’m always seeking to improve the contents. If you feel that one of these talks fits in your event theme or schedule, feel free to reach out!

SSL/TLS for Mortals

Using SSL/TLS the right way is often a big hurdle for developers. We prefer to have that one colleague perform "something with certificates", because he/she knows how that works. But what if "that one colleague" is enjoying vacation and something goes wrong with the certificates?

In this session we'll take a close look at secure communication at the transport level. Starting with what exactly SSL and TLS is, we'll dive into public/private keys, and signing. We'll also learn what all this has to do with an unfortunate Dutch notary. Of course, there'll be plenty of practical tips & trics, as well as demo's.

Attend this session to become "that one colleague"!

Conference Date
JAX '18 Wed Apr 25, 2018
Devoxx FR Thu Apr 19, 2018
DevNexus Fri Feb 23, 2018
JavaOne Wed Oct 04, 2017
Voxxed Days Luxembourg Thu Jun 22, 2017

How To Stay Responsive With 400 Backends

In these days of web scale and microservices, gracefully handling faulty or crashing web services becomes increasingly important. As long as your application uses just a handful of such external systems, there’s no problem. But what if you have hundreds of them? How will you prevent your application from the negative effects of inevitable incidental crashes or timeouts when contacting other systems?

In this talk, we'll take a real-world case from a web scale system. This system is targeted at 7 million users and has around 400 heterogeneous external integrations. Akka and Scala power a system that is capable of running smoothly even when some of these services might not be so stable. 

Conference Date
JVMCON Tue Jan 30, 2018
JBCNConf Tue Jun 20, 2017

Building cross-platform mobile apps with React Native

There's nothing more expensive than building the same thing twice. Yet that is what a lot of companies do when they publish a mobile app: they build one for Android and one for iOS. But wait, you don't have to! Using React Native, you can build one mobile app for both platforms from one code base using a language you're probably already familiar with - JavaScript.

In this session, we'll discuss building a simple word game app for both iOS and Android. First, we'll dive into how React Native works and how to build a basic application. Then, we'll dive into the Redux framework, which helps us building predictable state and allows for great testability of our application. Finally, we look at how the two integrate and how the game is built.

Conference Date
Devoxx Tue Nov 07, 2017
JFokus Wed Feb 08, 2017

Outsmarting the Smart Meter

Starting 2014, all Dutch households are receiving a "smart meter" to replace their old meter systems for electricity and gas. They're called "smart", but are they really? Most meters just send their data to a central point using GPRS. Using third party services, consumers can get an insight in their energy usage.

But we're technicians, we can build something better ourselves. All it takes is a prefab cable (or some soldering), code, patience and a beer. Using Scala plus Akka for the backend, TypeScript plus React for the frontend and Websockets for communication you can build your own energy dashboard. En passant, we might even see a little Akka stream dropping by.

Attend this session to discover how to outsmart your Smart Meter!

Conference Date
Reactive Amsterdam Tue Sep 25, 2018
Utrecht JUG Fri Oct 27, 2017
JFokus Wed Feb 08, 2017
Brabant.scala Thu Jul 07, 2016
JavaCro '16 Thu May 19, 2016
Info Support Wed May 04, 2016

ELK: BigData for DevOps

Big Data is often related to companies like Google, Facebook or Twitter. Indeed, 500 bilion tweets a day, 1,3 billion active Facebook users or 30 billion web pages to search, we're talking 'Big Data'. Many smaller companies have Big Data, too, without knowing it: application log files.

This talk discusses how to use Elasticsearch, Logstash and Kibana to gain insight in these data. Apart from the general picture, it covers a detailed walk-through of how to configure Logstash for filtering sensitive data from log files. It also covers a real-world example at a major Dutch bank, including common pit falls, best practices and lessons learned.

After attending this session you will be able to leverage the power of the ELK stack for your own application. Even for smaller companies and applications, a lot of knowledge can be gained from proper insight in your production environment.

Conference Date
JBCNConf Sat Jun 18, 2016
JavaCro '16 Thu May 19, 2016
Javantura v3 Sat Feb 20, 2016
ConFESS_2015 Tue Apr 14, 2015